1. Field of the Invention
This invention relates in general to apparatus and methods to assist in the fixation of soft tissue to bone, and more particularly to human anterior cruciate ligament (ACL) and canine cranial cruciate ligament (CrCL) reconstruction grafts.
2. Prior Art
Rupture of the cranial cruciate ligament (CrCL) and subsequent osteoarthritis is a leading cause of canine hind limb lameness. Numerous techniques have been described to stabilize the canine knee or stifle following CrCL rupture to inhibit or prevent osteoarthritis. One such technique is intra-articular CrCL graft reconstruction for stabilization of CrCL deficient stifles. Various devices for initial surgical graft fixation have been utilized. These include the EndoButton CL, the Bone Mulch Screw, the RigidFix, Interference Screws, the BioScrew, the RCI screw, the SmartScrew ACL, a Synthes 6.5 cancellous screw with a spiked plastic washer or a soft tissue fixation plate, as well as various type staples, including stone and barbed staples.
In CrCL reconstruction it is necessary to obtain a desired graft tension and then to secure the tensioned graft at the desired position on the bone. There remains in the current surgical procedure problems with obtaining the necessary graft fixation strength quickly to prevent loss of the desired graft tension. A second problem relates to the damage of the graft as it is being tensioned over the rough or sharp surfaces of the bone or fixation device used. In addition the fixation device must have the ability to maintain the graft tension during the normal activity of the person or animal during the recovery period.
In the surgical application of these devices it is necessary that the graft to be affixed to the bone have the desired tension. The current devices are more difficult to employ during the surgical procedures than is desired. Therefore, there remains a need for a soft tissue fixation device that can be used with known arthroscopic or open surgical techniques, does not require unique application equipment, can be used with various CrCL reconstruction materials, and can affix the graft to the bone quickly and easily while still permitting the desired graft tensioning.
Still further there remains a need to provide a device that is simple in construction and would allow the CrCL reconstruction graft to be tensioned and secured to the bone in a single step.